When should the fingers and toes be interlaced with water during Wudu, and is it permissible to interlace the fingers and toes during the second wash?

"Interlacing the fingers and toes is a Sunnah during ablution (ghusl). This Sunnah is achieved by performing it in any of the three washes. It is recommended to interlace in all three washes, based on the hadith of Uthman (may Allah be pleased with him) who interlaced between the toes of his feet three times and said: 'I saw the Messenger of Allah (peace and blessings be upon him) do as I have done.'"